The future of security tools has changed greatly for the last several years. Today the network must respond to network attacks maintaining the network reliability, business performance and cyberspace security. The aim of cyber security issue is to make the network more flexible in order to prevent attacks and to keep on working.

Network security is a primary issue for every company, organization or individual. There exist various types and levels of network attacks. The main differences between national, corporate and information cyber security lie in the level of network security and tools applied. The national data requires the highest possible level of network security. The corporation has to use a multilayered approach in order to protect the information located on the computer from network attacks. The level of information security depends on an organization, state or individual, who use it. Thus, the level of network security is defined according to this principle.

Department of Homeland Security and Cyberspace Security (DHS) has been created to improve the cyber security of America. DHS is responsible for developing the national plan for securing the state resources and infrastructure of the US; giving crisis management concerning cyber attacks; providing technical assistance to the government entities concerning emergency recovery plans of critical information systems; coordinating with agencies of the federal government to provide advice about appropriate protective measures to organizations including the private sector, academia, and the public; funding research that will lead to new technologies in support of homeland security.

Strategic principles of the National Homeland Security are directed at securing cyberspace via the following:

• Preventing cyber attacks against US infrastructures;

• reducing national vulnerability to cyberspace attacks;

• reducing the recovery time after a cyber attack occurs.

The national cyber space security has several priorities. They are:

1. The national cyberspace security response system. This system is public/private architecture for analyzing, warning and managing cyber incidents of national importance.

2. The national cyberspace security threat and vulnerability reduction program.

3. The national cyberspace security awareness and training program.

4. Government security cyberspace.

5. International cyberspace security program. It is aimed at preventing cyber attacks that could influence national security. This program improves the international response to attacks of such kind.